An aircraft, landing includes a touchdown, bringing the aircraft to taxi speed, and eventually bringing the aircraft to a complete stop. During a landing, commercial jet engines can continue to produce thrust causing the aircraft to move in a forward direction, even when idle, acting against deceleration of the aircraft. Brakes of landing gear of aircraft can be sufficient in normal circumstances to stop the aircraft, by themselves, but for safety purposes, and to reduce stress on the brakes, another deceleration method is often used. In scenarios involving bad weather, where factors like snow or rain on runways reduce effectiveness of brakes, and in emergencies like rejected takeoffs, the need for a secondary deceleration method is more pronounced.
An example secondary deceleration method is to reverse a direction of the exhaust stream of the jet engine and use the power of the engine itself to decelerate. Reverse thrust, also called thrust reversal, is a temporary diversion of an aircraft engine's thrust so that it is directed against a forward travel of the aircraft to provide deceleration. Thrust reverser systems are included on many aircraft to help slow down the aircraft after touch-down, which reduces wear on brakes and enables shorter landing distances.
Existing reverser systems typically enable a pilot to command reverse thrust, if needed, but do not optimize the level of reverse thrust provided. Thus, improvements are needed to optimize airplane landing efficiencies.